Power transmission device



Sept. 29, 193%. RAFTER 2,055,803

POWER TRANSMISSION DEVICE Filed July 24, 1955 2 Sheets-Sheet 1 lYlMll 44 47 Y. IVENIBB wQM ATTORN EY Patented Sept. 29, 1936 2,055,803

UNITED STATES PATENT OFFKIE POWER TRANSMISSION DEVICE Albert Rafter,Glen Ridge, N. J., assignor to Rafter Machine Company, Belleville, N.J., a partnership composed of Albert Rafter and John C. Rafter, Jr.

Application July 24, 1935, Serial No. 32,873

Claims. (Cl. 192-48) This invention relates to a power transmitting 14by means of which the tension or compression device and moreparticularly to a friction clutchof the springs and the forces exertedthereby can ing device which becomes ineffective for power be adjusted.transmitting purposes when the forces applied The springs and theadjusting elements are 5 thereto exceeda predetermined amount. confinedwithin a casing l5 which is secured to the In machines where largeforces are applied, it shaft 8 and rotates therewith by means of boltsoften happens that in some instances an exces- "5- sive force isapplied, which damages certain parts Referring to it Will be Seen thatthe of the machine, or causes the power transmitting Wheel 4 is p v W aplurality of ecesses parts to jam, and it is often necessary to comineach of Which is pivetally mounted a pawl 10 pletely dismantle themachine to restore it to its I7 011 a Suitable Stud normally edOutwardproper running order. In some machines, the re- 1y from hrecesses y a m i n sp n l8 pairing of such defects requires considerabletime h d y the Wheel Th ange 6 has its p and m and is 0bvi0us1yexpensive, riphery provided with a plurality of ratchet teeth It is anobject of this invention to provide a which e arranged to engage e pawlsI1 I51 power transmitting device in i h th power is when the wheel isrotated in one direction, the transmitted by friction means, said devicealso pawls ratcheting Over the te th When the wheel being provided withmeans to enable it to be effecis rotated in the ppos te direction.tively driven in an opposite direction to release In Operation, w poweris pp d to ause U the machine from a jamming condition caused the wheel4 to rotate in a counter-clockwise digo by an Overload rection,indicated by the arrow (see Fig. 1) the A further object is theprovision, in a friction flange 5 n h Wh 4 f i lly engages he powertransmitting device, of means for adjusting flange 5 to drive th latter,Which in n, through the amount of friction to enable the machine to thehub d ves the Shaft 8. When it is desired accommodate predeterminedbade, that the capacity of the power transmittingde- 25 These d otheradvantageous t hi h vice be decreased, or increased, the screws [4 arewill 1 t appear, are accomplished by t simple moved either out or inwith respect to the recesses and practical construction and arrangementof in p ate t0 y the pressure of the Springs H parts hereinafterdescribed and exhibited in the n the disc w c in turn var e p uaccompanying drawings, forming part hereof, and that is, the frictionalengagement between flanges 30 in which: 5 and Fig. 1 is an elevationalview of the power trans- S u the machine become Overloaded, the mittingdevice, frictional engagement between flanges 5 and 6 Fig. 2 is asectional View taken on line 2-2 of Will be broken and they will notmove together, Fig; 1, that is, they will slip, causing the pawls I! to35 Fi 3 i ti n l i showing a modified ratchet over the teeth l9 to makea noise, which form of adjusting means which can be used in will notifya attendant 0f the overload.

the d vi e, In many instances, an overload will cause parts Fig. 4 is asectional view of a modified form of Of a machine to become jammed ordamaged; and

the power transmitting device, and this situation usually can beremedied only by 40 Fig. 5 is a view taken on line 5-5 of Fig. 4.completely dismantling the machine. 7 Referring to the drawings, thedevice is shown However, with my device, in the event that certocomprise a driving wheel 4 which is provided tain parts of the machinehave become jammed with an internal flange 5 frictionally engaging thebecause of an overload, it is only necessary to reflange 6 of a huh Iwhich is keyed to the shaft 8. verse the direction of rotation of thewheel 4 to 45 The wheel 4 can be driven by a belt, gears, or cause it torotate in a clockwise direction (see any other wellknown driving medium.Fig. 1) so that the pawls I1 will engage the teeth A disc 9 is attachedto the hub l by a spline l0 l9 and drive the flange 6 and also the shaft8 in and is caused to exert a pressure upon the flange an oppositedirection to their normal directions 5 by a plurality of compressionsprings H which of rotation, which will release the machine from 50 arepositioned in recesses in the disc 9, and in the jammed condition.recesses in a plate I 2 which is secured to the hub In Fig. 3 is shown amodified form of adjusting l by means of a plurality of screws l3 orother means in which a ring 20 is provided with a suitable means.Threaded into the recesses in the plurality of bosses 2| receivingcompression springs plate l2 and abutting the springs H are screws 22.The plate I2 is provided with an annular 55 threaded slot which receivesa threaded ring 23, the latter bearing against the ring 20. When it isdesired to adjust the tension of the springs 22, the ring 23 is screwedinto or out of the slot in the plate I2.

From the above description it will be seen that I have provided acomparatively simple and efiective power transmitting device which canbe readily adjusted to accommodate predetermined loads, and which slipsand avoids damage to the machine upon which it is used when an overloadis applied. The device is also provided with the pawls I! and teeth l9to enable driving in a reverse direction when it is desired to releasethe machine from a jam caused by an overload.

In Figs. 4 and 5 is shown a modified form of the invention in which adriving wheel 40 has attached thereto an annulus 4| which comprises anelement of a one-way gripping device having a member 42 attached bymeans of a key 43 to the shaft 44. The member 42 has cut out portions 46along the periphery thereof in which are positioned rollers 45. It willbe seen, from Fig. 5, that when the annulus 4| is rotated clockwise, itwill have a wedging action upon the rollers 45, to cause the rollers totightly grip the member 42 so that the latter will rotate with themember 4| and transmit power to the shaft 44.

Keyed to the shaft 44 is a collar 50 which has attached thereto by meansof a key 49, a friction disk 41, which is provided with recesses toreceive compression springs 48 supported by the cover plate 5|. Thesprings 48 force the friction plate 41 into tight frictional engagementwith the wheel 40 to cause the wheel and disk 41 to rotate together.

When power is applied to cause the wheel 40 to rotate in acounterclockwise direction, the wheel transmits the power through thefriction disk 41 and collar 50 to the shaft 44. When the machine becomesoverloaded, frictional engagement between the wheel 40 and the disk 41will be broken; that is, they will slip relative to each other and theshaft 44 will cease to be driven. If the parts of the machine havebecome jammed or damaged, the wheel 40 can berotated in a clockwisedirection and power will be transmitted to the shaft 44 through theone-way gripping device comprising the annulus 4|, rollers 45 and member42. This reversal of direction of rotation of the shaft 44 will releasethe machine from the jammed condition.

The foregoing disclosure is to be regarded as descriptive andillustrative only, and not as restrictive or limitative of the inventionof which obviously an embodiment may be constructed including manymodifications, without departing from the general scope herein indicatedand denoted in the appended claims.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent, is:

1. A power transmitting device comprising a driving wheel having aflange, a driven shaft, a hub keyed to the shaft and having a flangeengaging the flange on the driving wheel, a disc splined to said hub,said disc bearing against the flange on the driving wheel, a plateattached to the hub, a plurality of compression springs supported bysaid plate and by the disc, said springs exerting pressure upon the discto cause the flange on the driving wheel to frictionally engage theflange on the hub, means to adjust the springs to regulate the pressureexerted thereby, and a one-way gripping device associated with saidwheel and hub to enable power to be transmitted from the wheel to thehub in one direction of rotation only.

2. A power transmitting device comprising a driving wheel, having aflange, a driven shaft, a hub keyed to the shaft and having a flangeengaging the flange on the driving wheel, a disc splined to said hub,said disc bearing against the flange on the driving wheel, a plateattached to the hub, a plurality of compression springs supported bysaid plate and by the disc, said springs exerting pressure upon the discto cause the flange on the driving wheel to frictionally engage theflange on the hub, and means to adjust the springs to regulate thepressure exerted thereby, said flange on the hub having a plurality ofratchet teeth about its periphery, a plurality of pawls pivotallysupported by the driving wheel, and means to urge the pawls to engagesaid ratchet teeth when the driving wheel is rotated in a predetermineddirection.

3. In a power transmitting device, a driving Wheel, a driven shaft, ahub attached to said shaft and having a flange frictionally engagingparts of the driving wheel, said flange having a plurality of ratchetteeth about its periphery, a plurality of pawls pivotally supported bythe driving wheel, and means carried by the driving wheel to urge thepawls into engagement with said ratchet teeth when the driving wheel isrotated in a certain direction.

4. In a power transmitting device, a driving wheel having a flange, adriven shaft, a hub attached to said shaft and having a flangefrictionally engaging the flange on the driving wheel, and spring meanscarried by the hub to exert pressure upon the flange of the drivingwheel, a plate supported by the hub and having an annular threaded slot,and a ring threaded into the slot, said ring adapted to engage thespring means to regulate the pressure exerted thereby.

5. A power transmitting device comprising a driving wheel having aflange, a driven shaft, a hub keyed to the shaft and having a flangeengaging the flange on the driving wheel, a disc encircling said shaftand slidably mounted, said disc bearing against the flange on thedriving wheel, a plate mounted at one end of the shaft, a plurality ofcompression springs supported by said plate and by the disc, saidsprings exerting pressure upon the disc to cause the flange on thedriving wheel to frictionally engage the flange on the hub, and aone-way gripping device associated with said wheel and shaft to enablepower to be transmitted from the wheel to the shaft in one direction ofrotation only.

ALBERT RAFTER.

